Powertrain for 5-speed automatic transmissions

Abstract

Disclosed is a powertrain used for a 5-speed automatic transmission. The powertrain includes a first compound planetary gearset and a second compound planetary gearset. The first compound planetary gearset comprises first and second simple planetary gearsets having first, second, third, and fourth operating elements, while the second compound planetary gearset comprises third and fourth simple planetary gearsets having fifth, sixth, seventh, and eighth operating elements. One of the fifth to eighth operating elements are fixedly connected to one of the first to fourth operating elements, one of the fifth to eighth operating elements are variably connected to two of the first to fourth operating elements, and one of the fifth to eighth operating elements operates as an output element. Clutches are disposed to variably connect the operating elements of the first and second compound planetary gearsets. A brake is interposed between at least one of the operating elements of the first and second compound planetary gearsets to a transmission housing.

What is claimed is: 
     
       1. A powertrain for a 5-speed automatic transmission comprising: a first compound planetary gearset comprising first and second simple planetary gearsets having first, second, third, and fourth operating elements, one of said operating elements acting as an input element;   a second compound planetary gearset comprising third and fourth simple planetary gearsets having fifth, sixth, seventh, and eighth operating elements, one of said fifth to eighth operating elements being fixedly connected to one of said first to fourth operating elements, one of said fifth to eighth operating elements being variably connected to two of said first to fourth operating elements, and one of said fifth to eighth operating elements operating as an output element;   clutch means for variably connecting said operating elements of the first and second compound planetary gearsets; and   brake means for selectively connecting at least one of the operating elements of the first and second compound planetary gearsets to a transmission housing.   
     
     
       2. The powertrain of claim 1, wherein said first compound planetary gearset is realized through a combination of the first and second simple planetary gearsets, and said second compound planetary gearset is realized through a combination of the third and fourth simple planetary gearsets, said first, second, third, and fourth simple planetary gearsets being double pinion planetary gearsets. 
     
     
       3. The powertrain of claim 2, wherein a sun gear and a ring gear of the first simple planetary gearset are fixedly connected respectively to a planet carrier and a ring gear of the second simple planetary gearset. 
     
     
       4. The powertrain of claim 2, wherein a sun gear and a ring gear of the third simple planetary gearset are fixedly connected respectively to a planet carrier and a ring gear of the fourth simple planetary gearset. 
     
     
       5. The powertrain of claim 2, wherein a sun gear of the second simple planetary gearset is fixedly connected to a planet carrier of the third simple planetary gearset, and ring gears of the third and fourth simple planetary gearsets are variably connected to both a planet carrier of the first simple planetary gearset, and to ring gears of the first and second simple planetary gearsets. 
     
     
       6. The powertrain of claim 3, wherein a sun gear of the second simple planetary gearset is fixedly connected to a planet carrier of the third simple planetary gearset, and ring gears of the third and fourth simple planetary gearsets are variably connected to both a planet carrier of the first simple planetary gearset, and to ring gears of the first and second simple planetary gearsets. 
     
     
       7. The powertrain of claim 4, wherein a sun gear of the second simple planetary gearset is fixedly connected to a planet carrier of the third simple planetary gearset, and the ring gears of the third and fourth simple planetary gearsets are variably connected to both a planet carrier of the first simple planetary gearset, and to ring gears of the first and second simple planetary gearsets. 
     
     
       8. The powertrain of claim 2, wherein a sun gear and a planet carrier of the third simple planetary gearset are fixedly connected respectively to a sun gear and a ring gear of the second simple planetary gearset. 
     
     
       9. The powertrain of claim 2, wherein a sun gear of the second simple planetary gearset is fixedly connected to a ring gear of the third simple planetary gearset, and both a planet carrier of the third and a ring gear of the fourth simple planetary gearsets are variably connected to a planet carrier of the first simple planetary gearset, and to ring gears of the first and second simple planetary gearset. 
     
     
       10. The powertrain of claim 4, wherein a sun gear of the second simple planetary gearset is fixedly connected to the ring gear of the third simple planetary gearset, and both a planet carrier of the third and the ring gear of the fourth simple planetary gearsets are variably connected to a planet carrier of the first simple planetary gearset, and to ring gears of the first and second simple planetary gearset. 
     
     
       11. The powertrain of claim 6, wherein the sun gear of the second simple planetary gearset is fixedly connected to a ring gear of the third simple planetary gearset, and both the planet carrier of the third and a ring gear of the fourth simple planetary gearsets are variably connected to a planet carrier of the first simple planetary gearset, and to ring gears of the first and second simple planetary gearset. 
     
     
       12. The powertrain of claim 2, wherein a planet carrier and a ring gear of the third simple planetary gearset are fixedly connected respectively to a ring gear and a planet carrier of the second simple planetary gearset. 
     
     
       13. The powertrain of claim 2, wherein a sun gear of the second simple planetary gearset is fixedly connected to a planet carrier and a ring gear of the third and fourth simple planetary gearsets, and both a ring gear of the third and a planet carrier of the fourth simple planetary gearsets are variably connected to a planet carrier of the first simple planetary gearset, and to ring gears of the first and second simple planetary gearset. 
     
     
       14. The powertrain of claim 4, wherein a sun gear of the second simple planetary gearset is fixedly connected to a planet carrier of the third and the ring gear of the fourth simple planetary gearsets, and both the ring gear and planet carrier of the third and fourth simple planetary gearsets are variably connected to a planet carrier of the first simple planetary gearset, and to ring gears of the first and second simple planetary gearset. 
     
     
       15. The powertrain of claim 8, wherein a sun gear of the second simple planetary gearset is fixedly connected to the planet carrier and a ring gear of the third and fourth simple planetary gearsets, and both the ring gear of the third and a planet carrier of the fourth simple planetary gearsets are variably connected to a planet carrier of the first simple planetary gearset, and to ring gears of the first and second simple planetary gearset. 
     
     
       16. The powertrain of claim 1, wherein the first compound planetary gearset is realized through a combination of the first and second simple planetary gearset, both of which are double pinion planetary gearsets, and the second compound planetary gearset is realized through a combination of the third simple planetary gearset, which is a double pinion planetary gearset, with the fourth simple planetary gearset, which is a single pinion planetary gearset. 
     
     
       17. The powertrain of claim 10, wherein a sun gear and a ring gear of the first simple planetary gearset are fixedly connected respectively to a planet carrier and a ring gear of the second simple planetary gearset. 
     
     
       18. The powertrain of claim 10, wherein a planet carrier and a ring gear of the third simple planetary gearset are fixedly connected respectively to a planet carrier and a ring gear of the fourth simple planetary gearset. 
     
     
       19. The powertrain of claim 10, wherein a sun gear of the second simple planetary gearset is fixedly connected to ring gears of the third and fourth simple planetary gearsets, and planet carriers of the third and fourth simple planetary gearsets are variably connected to a planet carrier of the first simple planetary gearset, and to ring gears of the first and second simple planetary gearset. 
     
     
       20. The powertrain of claim 11, wherein a sun gear of the second simple planetary gearset is fixedly connected to ring gears of the third and fourth simple planetary gearsets, and planet carriers of the third and fourth simple planetary gearsets are variably connected to a planet carrier of the first simple planetary gearset, and to the ring gears of the first and second simple planetary gearset. 
     
     
       21. The powertrain of claim 12, wherein a sun gear of the second simple planetary gearset is fixedly connected to the ring gears of the third and fourth simple planetary gearsets, and the planet carriers of the third and fourth simple planetary gearsets are variably connected to a planet carrier of the first simple planetary gearset, and to ring gears of the first and second simple planetary gearset. 
     
     
       22. The powertrain of claim 10, wherein a planet carrier and a ring gear of the third simple planetary gearset are fixedly connected respectively to a planet carrier and a ring gear of the second simple planetary gearset. 
     
     
       23. The powertrain of claim 10, wherein sun gears of the first and second simple planetary gearsets are fixedly connected to a planet carrier of the third simple planetary gearset, and ring gears of the third and fourth simple planetary gearsets are variably connected to a planet carrier of the first simple planetary gearset, and to ring gears of the first and second simple planetary gearset. 
     
     
       24. The powertrain of claim 11, wherein sun gears of the first and second simple planetary gearsets are fixedly connected to the planet carrier of the third simple planetary gearset, and ring gears of the third and fourth simple planetary gearsets are variably connected to a planet carrier of the first simple planetary gearset, and to the ring gears of the first and second simple planetary gearset. 
     
     
       25. The powertrain of claim 10, wherein a sun gear and a planet carrier of the third simple planetary gearset are fixedly connected respectively to a sun gear and a planet carrier of the second simple planetary gearset. 
     
     
       26. The powertrain of claim 10, wherein a sun gear of the second simple planetary gearset is fixedly connected to planet carriers of the third and fourth simple planetary gearsets, and ring gears of the third and fourth simple planetary gearsets are variably connected to both a planet carrier of the first simple planetary gearset, and to ring gears of the first and second simple planetary gearsets. 
     
     
       27. The powertrain of claim 11, wherein a sun gear of the second simple planetary gearset is fixedly connected to planet carriers of the third and fourth simple planetary gearsets, and ring gears of the third and fourth simple planetary gearsets are variably connected to both a planet carrier of the first simple planetary gearset, and to the ring gears of the first and second simple planetary gearsets. 
     
     
       28. The powertrain of claim 16, wherein the sun gear of the second simple planetary gearset is fixedly connected to planet carriers of the third and fourth simple planetary gearsets, and ring gears of the third and fourth simple planetary gearsets are variably connected to both a planet carrier of the first simple planetary gearset, and to ring gears of the first and second simple planetary gearsets. 
     
     
       29. The powertrain of claim 1, wherein the first compound planetary gearset is realized through a combination of the first and second simple planetary gearset, both of which are double pinion planetary gearsets, and the second compound planetary gearset is realized through a combination of the third simple planetary gearset, which is a single pinion planetary gearset, with the fourth simple planetary gearset, which is a double pinion planetary gearset. 
     
     
       30. The powertrain of claim 18, wherein a sun gear and a ring gear of the first simple planetary gearset are fixedly connected respectively to a planet carrier and a ring gear of the second simple planetary gearset. 
     
     
       31. The powertrain of claim 18, wherein a sun gear and a ring gear of the third simple planetary gearset are fixedly connected respectively to a sun gear and a ring gear of the fourth simple planetary gearset. 
     
     
       32. The powertrain of claim 19, wherein a sun gear of the second simple planetary gearset is fixedly connected to a planet carrier of the third simple planetary gearset, and ring gears of the third and fourth simple planetary gearsets are variably connected to both a planet carrier of the first simple planetary gearset, and to the ring gears of the first and second simple planetary gearsets. 
     
     
       33. The powertrain of claim 20, wherein a sun gear of the second simple planetary gearset is fixedly connected to a planet carrier of the third simple planetary gearset, and the ring gears of the third and fourth simple planetary gearsets are variably connected to both a planet carrier of the first simple planetary gearset, and to ring gears of the first and second simple planetary gearsets. 
     
     
       34. The powertrain of claim 18, wherein a planet carrier and a ring gear of the third simple planetary gearset are fixedly connected respectively to a ring gear and a sun gear of the second simple planetary gearset. 
     
     
       35. The powertrain of claim 18, wherein sun gears of the first and second simple planetary gearsets are fixedly connected to both a planet carrier of the third and a ring gear of the fourth simple planetary gearsets, and a planet carrier of the fourth simple planetary gearset is variably connected to both a planet carrier of the first simple planetary gearset, and to ring gears of the first and second simple planetary gearsets. 
     
     
       36. The powertrain of claim 19, wherein sun gears of the first and second simple planetary gearsets are fixedly connected to both a planet carrier of the third and a ring gear of the fourth simple planetary gearsets, and a planet carrier of the fourth simple planetary gearset is variably connected to both a planet carrier of the first simple planetary gearset, and to the ring gears of the first and second simple planetary gearsets. 
     
     
       37. The powertrain of claim 22, wherein sun gears of the first and second simple planetary gearsets are fixedly connected to both the planet carrier of the third and the ring gear of the fourth simple planetary gearsets, and a planet carrier of the fourth simple planetary gearset is variably connected to both a planet carrier of the first simple planetary gearset, and to ring gears of the first and second simple planetary gearsets. 
     
     
       38. The powertrain of claim 2, wherein a sun gear and a planet carrier of the third simple planetary gearset are fixedly connected respectively to a planet carrier and a ring gear of the fourth simple planetary gearset. 
     
     
       39. The powertrain of claim 18, wherein a sun gear of the second simple planetary gearset is fixedly connected to a ring gear of the fourth simple planetary gearset, and both a planet carrier and a ring gear of the third and fourth simple planetary gearsets are variably connected to both a planet carrier of the first simple planetary gearset, and to ring gears of the first and second simple planetary gearsets. 
     
     
       40. The powertrain of claim 19, wherein a sun gear of the second simple planetary gearset is fixedly connected to a ring gear of the fourth simple planetary gearset, and both a planet carrier and a ring gear of the third and fourth simple planetary gearsets are variably connected to both a planet carrier of the first simple planetary gearset, and to the ring gears of the first and second simple planetary gearsets. 
     
     
       41. The powertrain of claim 24, wherein a sun gear of the second simple planetary gearset is fixedly connected to the ring gear of the fourth simple planetary gearset, and both the planet carrier and ring gear of the third and fourth simple planetary gearsets are variably connected to both a planet carrier of the first simple planetary gearset, and to ring gears of the first and second simple planetary gearsets. 
     
     
       42. The powertrain of claim 1, wherein the first compound planetary gearset is realized through a combination of the first and second simple planetary gearsets, both of which are double pinion planetary gearsets, and the second compound planetary gearset is realized through a combination of the third and fourth compound planetary gearsets, both of which are single pinion planetary gearsets. 
     
     
       43. The powertrain of claim 25, wherein a sun gear and a ring gear of the first simple planetary gearset are fixedly connected respectively to a planet carrier and a ring gear of the second simple planetary gearset. 
     
     
       44. The powertrain of claim 25, wherein a sun gear and a planet carrier of the third simple planetary gearset are fixedly connected respectively to a ring gear and a planet carrier of the fourth simple planetary gearset. 
     
     
       45. The powertrain of claim 25, wherein a sun gear of the second simple planetary gearset is fixedly connected to planet carriers of the third and fourth simple planetary gearsets, and a ring gear of the third simple planetary gearset is variably connected to both a planet carrier of the first simple planetary gearset, and to ring gears of the first and second simple planetary gearsets. 
     
     
       46. The powertrain of claim 26, wherein a sun gear of the second simple planetary gearset is fixedly connected to planet carriers of the third and fourth simple planetary gearsets, and a ring gear of the third simple planetary gearset is variably connected to both a planet carrier of the first simple planetary gearset, and to the ring gears of the first and second simple planetary gearsets. 
     
     
       47. The powertrain of claim 27, wherein a sun gear of the second simple planetary gearset is fixedly connected to the planet carriers of the third and fourth simple planetary gearsets, and a ring gear of the third simple planetary gearset is variably connected to both a planet carrier of the first simple planetary gearset, and to ring gears of the first and second simple planetary gearsets. 
     
     
       48. The powertrain of claim 2, wherein a planet carrier and a ring gear of the third simple planetary gearset are fixedly connected respectively to a ring gear and a planet carrier of the fourth simple planetary gearset. 
     
     
       49. The powertrain of claim 25, wherein a sun gear of the second simple planetary gearset is fixedly connected to a planet carrier of the third and a ring gear of the fourth simple planetary gearsets, and both a ring gear of the third and a planet carrier of the fourth simple planetary gearsets are variably connected to both a planet carrier of the first simple planetary gearset, and to ring gears of the first and second simple planetary gearsets. 
     
     
       50. The powertrain of claim 26, wherein a sun gear of the second simple planetary gearset is fixedly connected to a planet carrier and a ring gear of the third and fourth simple planetary gearsets, and both a ring gear of the third and a planet carrier of the fourth simple planetary gearsets are variably connected to both a planet carrier of the first simple planetary gearset, and to the ring gears of the first and second simple planetary gearsets. 
     
     
       51. The powertrain of claim 29, wherein a sun gear of the second simple planetary gearset is fixedly connected to the planet carrier of the third and the ring gear of the fourth simple planetary gearsets, and both the ring gear of the third and the planet carrier of the fourth simple planetary gearsets are variably connected to both a planet carrier of the first simple planetary gearset, and to ring gears of the first and second simple planetary gearsets. 
     
     
       52. The powertrain of claim 1, wherein the first compound planetary gearset is realized through a combination of the first simple planetary gearset, which is a double pinion planetary gearset, with the second simple planetary gearset, which is a single pinion planetary gearset; and the second compound planetary gearset is realized through a combination of the third and fourth simple planetary gearsets, both of which are single pinion planetary gearsets. 
     
     
       53. The powertrain of claim 31, wherein a planet carrier and a ring gear of the first simple planetary gearset are fixedly connected respectively to a planet carrier and a sun gear of the second simple planetary gearset. 
     
     
       54. The powertrain of claim 31, wherein a sun gear and a planet carrier of the third simple planetary gearset are fixedly connected respectively to a ring gear and a planet carrier of the fourth simple planetary gearset. 
     
     
       55. The powertrain of claim 31, wherein a ring gear of the second simple planetary gearset is fixedly connected to planet carriers of the third and fourth simple planetary gearsets, and a ring gear of the third simple planetary gearset is variably connected to both planet carriers of the first and second simple planetary gearsets, and to a ring gear of the first and a sun gear of the second simple planetary gearsets. 
     
     
       56. The powertrain of claim 32, wherein a ring gear of the second simple planetary gearset is fixedly connected to planet carriers of the third and fourth simple planetary gearsets, and a ring gear of the third simple planetary gearset is variably connected to both the planet carriers of the first and second simple planetary gearsets, and to the ring gear and sun gear of the first and second simple planetary gearsets. 
     
     
       57. The powertrain of claim 33, wherein a ring gear of the second simple planetary gearset is fixedly connected to the planet carriers of the third and fourth simple planetary gearsets, and a ring gear of the third simple planetary gearset is variably connected to both planet carriers of the first and second simple planetary gearsets, and to a ring gear and a sun gear of the first and second simple planetary gearsets. 
     
     
       58. The powertrain of claim 31, wherein a planet carrier and a ring gear of the third simple planetary gearset are fixedly connected respectively to a ring gear and a planet carrier of the fourth simple planetary gearset. 
     
     
       59. The powertrain of claim 31, wherein a ring gear of the second simple planetary gearset is fixedly connected to a planet carrier of the third and a ring gear of the fourth simple planetary gearsets, and both a ring gear of the third and a planet carrier of the fourth simple planetary gearsets are variably connected to both planet carriers of the first and second simple planetary gearsets, and to a ring gear of the first and a sun gear of the second simple planetary gearsets. 
     
     
       60. The powertrain of claim 32, wherein a ring gear of the second simple planetary gearset is fixedly connected to a planet carrier of the third and a ring gear of the fourth simple planetary gearsets, and both a ring gear of the third and a planet carrier of the fourth simple planetary gearsets are variably connected to both the planet carriers of the first and second simple planetary gearsets, and to the ring gear of the first and the sun gear of the second simple planetary gearsets. 
     
     
       61. The powertrain of claim 35, wherein a ring gear of the second simple planetary gearset is fixedly connected to the planet carrier of the third and the ring gear of the fourth simple planetary gearsets, and both the ring gear of the third and the planet carrier of the fourth simple planetary gearsets are variably connected to both planet carriers of the first and second simple planetary gearsets, and to a ring gear of the first and a sun gear of the second simple planetary gearsets. 
     
     
       62. The powertrain of claim 1, wherein the first compound planetary gearset is realized through a combination of the first simple planetary gearset, which is a double pinion planetary gearset, with the second simple planetary gearset, which is a single pinion planetary gearset; and the second compound planetary gearset is realized through a combination of the third simple planetary gearset, which is a single pinion planetary gearset, with the fourth simple planetary gearset, which is a double pinion planetary gearset. 
     
     
       63. The powertrain of claim 37, wherein a planet carrier and a ring gear of the first simple planetary gearset are fixedly connected respectively to a planet carrier and a sun gear of the second simple planetary gearset. 
     
     
       64. The powertrain of claim 37, wherein a sun gear and a ring gear of the third simple planetary gearset are fixedly connected respectively to a sun gear and a ring gear of the fourth simple planetary gearset. 
     
     
       65. The powertrain of claim 37, wherein ring gears of the first and second simple planetary gearsets are fixedly connected to a planet carrier of the third simple planetary gearset, and ring gears of the third and fourth simple planetary gearsets are variably connected to both planet carriers of the first and second simple planetary gearsets, and to a ring gear of the first and a sun gear of the second simple planetary gearspts. 
     
     
       66. The powertrain of claim 38, wherein ring gears of the first and second simple planetary gearsets are fixedly connected to a planet carrier of the third simple planetary gearset, and ring gears of the third and fourth simple planetary gearsets are variably connected to both the planet carriers of the first and second simple planetary gearsets, and to the ring gear of the first and the sun gear of the second simple planetary gearsets. 
     
     
       67. The powertrain of claim 39, wherein ring gears of the first and second simple planetary gearsets are fixedly connected to a planet carrier of the third simple planetary gearset, and the ring gears of the third and fourth simple planetary gearsets are variably connected to both planet carriers of the first and second simple planetary gearsets, and to a ring gear of the first and a sun gear of the second simple planetary gearsets. 
     
     
       68. The powertrain of claim 37, wherein a planet carrier and a ring gear of the third simple planetary gearset are fixedly connected respectively to a ring gear and a sun gear of the second simple planetary gearset. 
     
     
       69. The powertrain of claim 37, wherein a ring gear of the second simple planetary gearset is fixedly connected to a planet carrier of the third and a ring gear of the fourth simple planetary gearsets, and a planet carrier of the fourth simple planetary gearset is variably connected to planet carriers of the first and second simple planetary gearsets, and to a ring gear of the first and a sun gear of the second simple planetary gearsets. 
     
     
       70. The powertrain of claim 39, wherein a ring gear of the second simple planetary gearset is fixedly connected to a planet carrier of the third and the ring gear of the fourth simple planetary gearsets, and a planet carrier of the fourth simple planetary gearset is variably connected to planet carriers of the first and second simple planetary gearsets, and to a ring gear of the first and a sun gear of the second simple planetary gearsets. 
     
     
       71. The powertrain of claim 41, wherein the ring gear of the second simple planetary gearset is fixedly connected to the planet carrier of the third and a ring gear of the fourth simple planetary gearsets, and a planet carrier of the fourth simple planetary gearset is variably connected to planet carriers of the first and second simple planetary gearsets, and to a ring gear of the first and the sun gear of the second simple planetary gearsets. 
     
     
       72. The powertrain of claim 37, wherein a sun gear and a planet carrier of the third simple planetary gearset are fixedly connected respectively to a planet carrier and a ring gear of the fourth simple planetary gearset. 
     
     
       73. The powertrain of, claim 37, wherein a ring gear of the second simple planetary gearset is fixedly connected to a ring gear of the fourth simple planetary gearset, and both a planet carrier of the third and a ring gear of the fourth simple planetary gearsets are variably connected to planet carriers of the first and second simple planetary gearsets, and to a ring gear of the first and a sun gear of the second simple planetary gearsets. 
     
     
       74. The powertrain of claim 38, wherein a ring gear of the second simple planetary gearset is fixedly connected to a ring gear of the fourth simple planetary gearset, and both a planet carrier of the third and the ring gear of the fourth simple planetary gearsets are variably connected to planet carriers of the first and second simple planetary gearsets, and to the ring gear of the first and the sun gear of the second simple planetary gearsets. 
     
     
       75. The powertrain of claim 43, wherein a ring gear of the second simple planetary gearset is fixedly connected to the ring gear of the fourth simple planetary gearset, and both the planet carrier of the third and the ring gear of the fourth simple planetary gearsets are variably connected to planet carriers of the first and second simple planetary gearsets, and to a ring gear of the first and a sun gear of the second simple planetary gearsets. 
     
     
       76. The powertrain of claim 1, wherein the first compound planetary gearset is realized through a combination of the first simple planetary gearset, which is a double pinion planetary gearset, with the second simple planetary gearset, which is a single pinion planetary gearset; and the second compound planetary gearset is realized through a combination of the third simple planetary gearset, which is a double pinion planetary gearset, with the fourth simple planetary gearset, which is a single pinion planetary gearset. 
     
     
       77. The powertrain of claim 46, wherein a planet carrier and a ring gear of the first simple planetary gearset are fixedly connected respectively to a planet carrier and a sun gear of the second simple planetary gearset. 
     
     
       78. The powertrain of claim 45, wherein a planet carrier and a ring gear of the third simple planetary gearset are fixedly connected respectively to a planet carrier and a ring gear of the fourth simple planetary gearset. 
     
     
       79. The powertrain of claim 45, wherein ring gears of the first and second simple planetary gearsets are fixedly connected to ring gears of the third and fourth simple planetary gearsets, and planet carriers of the third and fourth simple planetary gearsets are variably connected to both planet carriers of the first and second simple planetary gearsets, and to the ring gear of the first and a sun gear of the second simple planetary gearsets. 
     
     
       80. The powertrain of claim 46, wherein ring gears of the first and second simple planetary gearsets are fixedly connected to ring gears of the third and fourth simple planetary gearsets, and planet carriers of the third and fourth simple planetary gearsets are variably connected to both the planet carriers of the first and second simple planetary gearsets, and to the ring gear of the first and the sun gear of the second simple planetary gearsets. 
     
     
       81. The powertrain of claim 47, wherein ring gears of the first and second simple planetary gearsets are fixedly connected to the ring gears of the third and fourth simple planetary gearsets, and the planet carriers of the third and fourth simple planetary gearsets are variably connected to both planet carriers of the first and second simple planetary gearsets, and to the ring gear of the first and a sun gear of the second simple planetary gearsets. 
     
     
       82. The powertrain of claim 45, wherein a planet carrier and a ring gear of the third simple planetary gearset are fixedly connected respectively to a planet carrier and a ring gear of the second simple planetary gearset. 
     
     
       83. The powertrain of claim 46, wherein ring gears of the first and second simple planetary gearsets are fixedly connected to a planet carrier of the third simple planetary gearset, and ring gears of the third and fourth simple planetary gearsets are variably connected to both planet carriers of the first and second simple planetary gearsets, and to the ring gear of the first and the sun gear of the second simple planetary gearsets. 
     
     
       84. The powertrain of claim 45, wherein ring gears of the first and second simple planetary gearsets are fixedly connected to the planet carrier of the third simple planetary gearset, and ring gears of the third and fourth simple planetary gearsets are variably connected to both planet carriers of the first and second simple planetary gearsets, and to the ring gear of the first and a sun gear of the second simple planetary gearsets. 
     
     
       85. The powertrain of claim 45, wherein ring gears of the first and second simple planetary gearsets are fixedly connected to planet carriers of the third and fourth simple planetary gearsets, and ring gears of the third and fourth simple planetary gearsets are variably connected to both planet carriers of the first and second simple planetary gearsets, and to the ring gear of the first and a sun gear of the second simple planetary gearsets. 
     
     
       86. The powertrain of claim 46, wherein ring gears of the first and second simple planetary gearsets are fixedly connected to planet carriers of the third and fourth simple planetary gearsets, and ring gears of the third and fourth simple planetary gearsets are variably connected to both the planet carriers of the first and second simple planetary gearsets, and to the ring gear of the first and the sun gear of the second simple planetary gearsets. 
     
     
       87. The powertrain of claim 51, wherein ring gears of the first and second simple planetary gearsets are fixedly connected to planet carriers of the third and fourth simple planetary gearsets, and ring gears of the third and fourth simple planetary gearsets are variably connected to both planet carriers of the first and second simple planetary gearsets, and to the ring gear of the first and the sun gear of the second simple planetary gearsets. 
     
     
       88. The powertrain of claim 1, wherein the first compound planetary gearset is realized through a combination of the first simple planetary gearset, which is a double pinion planetary gearset, with the second simple planetary gearset, which is a single pinion planetary gearset; and the second compound planetary gearset is realized through a combination of the third and fourth simple planetary gearsets, which are double pinion planetary gearsets. 
     
     
       89. The powertrain of claim 53, wherein a sun gear and a ring gear of the third simple planetary gearset are fixedly connected respectively to a planet carrier and a ring gear of the fourth simple planetary gearset. 
     
     
       90. The powertrain of claim 53, wherein a ring gear of the second simple planetary gearset is fixedly connected to a planet carrier of the third simple planetary gearset, and ring gears of the third and fourth simple planetary gearsets are variably connected to both planet carriers of the first and second simple planetary gearsets, and to a ring gear of the first and a sun gear of the second simple planetary gearsets. 
     
     
       91. The powertrain of claim 54, wherein a ring gear of the second simple planetary gearset is fixedly connected to a planet carrier of the third simple planetary gearset, and ring gears of the third and fourth simple planetary gearsets are variably connected to both the planet carriers of the first and second simple planetary gearsets, and to the ring gear of the first and the sun gear of the second simple planetary gearsets. 
     
     
       92. The powertrain of claim 55, wherein a ring gear of the second simple planetary gearset is fixedly connected to a planet carrier of the third simple planetary gearset, and the ring gears of the third and fourth simple planetary gearsets are variably connected to both planet carriers of the first and second simple planetary gearsets, and to a ring gear of the first and a sun gear of the second simple planetary gearsets. 
     
     
       93. The powertrain of claim 53, wherein a sun gear and a planet carrier of the third simple planetary gearset are fixedly connected respectively to a sun gear and a ring gear of the second simple planetary gearset. 
     
     
       94. The powertrain of claim 53, wherein a ring gear of the second simple planetary gearset is fixedly connected to a ring gear of the third simple planetary gearset, and a planet carrier of the third and a ring gear of the fourth simple planetary gearsets are variably connected to both planet carriers of the first and second simple planetary gearsets, and to a ring gear of the first and a sun gear of the second simple planetary gearsets. 
     
     
       95. The powertrain of claim 54, wherein a ring gear of the second simple planetary gearset is fixedly connected to a ring gear of the third simple planetary gearset, and a planet carrier of the third and a ring gear of the fourth simple planetary gearsets are variably connected to both the planet carriers of the first and second simple planetary gearsets, and to the ring gear of the first and the sun gear of the second simple planetary gearsets. 
     
     
       96. The powertrain of claim 57, wherein the ring gear of the second simple planetary gearset is fixedly connected to a ring gear of the third simple planetary gearset, and the planet carrier of the third and a ring gear of the fourth simple planetary gearsets are variably connected to both planet carriers of the first and second simple planetary gearsets, and to a ring gear of the first and the sun gear of the second simple planetary gearsets. 
     
     
       97. The powertrain of claim 53, wherein a planet carrier and a ring gear of the third simple planetary gearset are fixedly connected respectively to a ring gear and a planet carrier of the second simple planetary gearset. 
     
     
       98. The powertrain of claim 53, wherein ring gears of the first and second simple planetary gearset are fixedly connected to a planet carrier of the third and a ring gear of the fourth simple planetary gearsets, and a ring gear of the third and a planet carrier of the fourth simple planetary gearsets are variably connected to both planet carriers of the first and second simple planetary gearsets, and to the ring gear of the first and a sun gear of the second simple planetary gearsets. 
     
     
       99. The powertrain of claim 54, wherein ring gears of the first and second simple planetary gearset are fixedly connected to a planet carrier of the third and a ring gear of the fourth simple planetary gearsets, and a ring gear of the third and a planet carrier of the fourth simple planetary gearsets are variably connected to both the planet carriers of the first and second simple planetary gearsets, and to the ring gear of the first and the sun gear of the second simple planetary gearsets. 
     
     
       100. The powertrain of claim 59, wherein ring gears of the first and second simple planetary gearset are fixedly connected to the planet carrier of the third and a ring gear of the fourth simple planetary gearsets, and a ring gear of the third and a planet carrier of the fourth simple planetary gearsets are variably connected to both planet carriers of the first and second simple planetary gearsets, and to the ring gear of the first and the sun gear of the second simple planetary gearsets.